diff mbox

dmaengine: omap-dma: Enable burst and data pack for SG

Message ID 20160916105315.28320-1-peter.ujfalusi@ti.com (mailing list archive)
State New, archived
Headers show

Commit Message

Peter Ujfalusi Sept. 16, 2016, 10:53 a.m. UTC 
From: Misael Lopez Cruz <misael.lopez@ti.com>

Enable the burst and data pack modes for the scatter-gather
in order to improve the throughput of the data transfers.

The improvement has been verified with MMC HS200 mode in
the DRA72 EVM using the iozone tool to compare the read
throughput (in kB/s) with and without burst/pack for
different reclens (in kB).

                              With
    reclen    Baseline   sDMA burst/pack
    ------    --------   ---------------
       64       46568         50820
      128       57564         63413
      256       65634         74937
      512       72427         83483
     1024       74563         84504
     2048       76265         86079
     4096       78045         87335
     8192       78989         88154
    16384       81265         91034

Signed-off-by: Misael Lopez Cruz <misael.lopez@ti.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
 drivers/dma/omap-dma.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

Comments

Vinod Koul Oct. 1, 2016, 6:05 a.m. UTC | #1 
On Fri, Sep 16, 2016 at 01:53:15PM +0300, Peter Ujfalusi wrote:
> From: Misael Lopez Cruz <misael.lopez@ti.com>
> 
> Enable the burst and data pack modes for the scatter-gather
> in order to improve the throughput of the data transfers.
> 
> The improvement has been verified with MMC HS200 mode in
> the DRA72 EVM using the iozone tool to compare the read
> throughput (in kB/s) with and without burst/pack for
> different reclens (in kB).
> 
>                               With
>     reclen    Baseline   sDMA burst/pack
>     ------    --------   ---------------
>        64       46568         50820
>       128       57564         63413
>       256       65634         74937
>       512       72427         83483
>      1024       74563         84504
>      2048       76265         86079
>      4096       78045         87335
>      8192       78989         88154
>     16384       81265         91034

Applied, thanks
diff mbox

Patch

diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c
index 1b7f5f32bf74..7ca27d4b1c54 100644
--- a/drivers/dma/omap-dma.c
+++ b/drivers/dma/omap-dma.c
@@ -904,13 +904,16 @@  static struct dma_async_tx_descriptor *omap_dma_prep_slave_sg(
 	d->es = es;
 
 	d->ccr = c->ccr | CCR_SYNC_FRAME;
-	if (dir == DMA_DEV_TO_MEM)
+	if (dir == DMA_DEV_TO_MEM) {
 		d->ccr |= CCR_DST_AMODE_POSTINC | CCR_SRC_AMODE_CONSTANT;
-	else
+		d->csdp = CSDP_DST_BURST_64 | CSDP_DST_PACKED;
+	} else {
 		d->ccr |= CCR_DST_AMODE_CONSTANT | CCR_SRC_AMODE_POSTINC;
+		d->csdp = CSDP_SRC_BURST_64 | CSDP_SRC_PACKED;
+	}
 
 	d->cicr = CICR_DROP_IE | CICR_BLOCK_IE;
-	d->csdp = es;
+	d->csdp |= es;
 
 	if (dma_omap1()) {
 		d->cicr |= CICR_TOUT_IE;